Harden MP vs eCPS comparison diagnostics

[MaxGhenis]

Summary

• report protected-family and family-breakdown losses on the same scale as the headline MP vs eCPS loss
• expose refit convergence, iteration counts, and recent train-loss progress in the comparison payload
• add useful support-audit panels for marketplace enrollment, age buckets, and MFS high-AGI gaps while suppressing zero-only secondary panels
• tighten PE-native simplex projection so population-sized weight sums cannot drift under default np.isclose relative tolerance

Tests

• uv run --python 3.13 ruff check src/microplex_us/pipelines/ecps_replacement_comparison.py src/microplex_us/pipelines/pe_native_optimization.py tests/pipelines/test_ecps_replacement_comparison.py tests/pipelines/test_pe_native_optimization.py
• uv run --python 3.13 ruff format --check src/microplex_us/pipelines/ecps_replacement_comparison.py src/microplex_us/pipelines/pe_native_optimization.py tests/pipelines/test_ecps_replacement_comparison.py tests/pipelines/test_pe_native_optimization.py
• uv run --python 3.13 --extra dev --extra policyengine python -m pytest tests/pipelines/test_ecps_replacement_comparison.py tests/pipelines/test_pe_native_optimization.py -q